diff --git a/backup/controller/backup_controller.class.php b/backup/controller/backup_controller.class.php
index cf5fcf96622..52793b24d68 100644
--- a/backup/controller/backup_controller.class.php
+++ b/backup/controller/backup_controller.class.php
@@ -55,6 +55,7 @@ class backup_controller extends base_controller {
 
     protected $status; // Current status of the controller (created, planned, configured...)
 
+    /** @var backup_plan */
     protected $plan;   // Backup execution plan
     protected $includefiles; // Whether this backup includes files or not.
 
diff --git a/backup/moodle2/backup_plugin.class.php b/backup/moodle2/backup_plugin.class.php
index 6a060abf8fb..32f6c1ddf23 100644
--- a/backup/moodle2/backup_plugin.class.php
+++ b/backup/moodle2/backup_plugin.class.php
@@ -34,13 +34,27 @@ defined('MOODLE_INTERNAL') || die();
  */
 abstract class backup_plugin {
 
+    /** @var string */
     protected $plugintype;
+    /** @var string */
     protected $pluginname;
+    /** @var string */
     protected $connectionpoint;
+    /** @var backup_optigroup_element */
     protected $optigroup; // Optigroup, parent of all optigroup elements
+    /** @var backup_structure_step */
     protected $step;
+    /** @var backup_course_task|backup_activity_task */
     protected $task;
 
+    /**
+     * backup_plugin constructor.
+     *
+     * @param string $plugintype
+     * @param string $pluginname
+     * @param backup_optigroup_element $optigroup
+     * @param backup_structure_step $step
+     */
     public function __construct($plugintype, $pluginname, $optigroup, $step) {
         $this->plugintype = $plugintype;
         $this->pluginname = $pluginname;
diff --git a/backup/moodle2/backup_stepslib.php b/backup/moodle2/backup_stepslib.php
index 11dd4ce9c78..49daa6fb41f 100644
--- a/backup/moodle2/backup_stepslib.php
+++ b/backup/moodle2/backup_stepslib.php
@@ -125,10 +125,9 @@ abstract class backup_activity_structure_step extends backup_structure_step {
 }
 
 /**
- * Abstract structure step, to be used by all the activities using core questions stuff
- * (namely quiz module), supporting question plugins, states and sessions
+ * Helper code for use by any plugin that stores question attempt data that it needs to back up.
  */
-abstract class backup_questions_activity_structure_step extends backup_activity_structure_step {
+trait backup_questions_attempt_data_trait {
 
     /**
      * Attach to $element (usually attempts) the needed backup structures
@@ -200,6 +199,17 @@ abstract class backup_questions_activity_structure_step extends backup_activity_
 }
 
 
+/**
+ * Abstract structure step to help activities that store question attempt data.
+ *
+ * @copyright 2011 The Open University
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+abstract class backup_questions_activity_structure_step extends backup_activity_structure_step {
+    use backup_questions_attempt_data_trait;
+}
+
+
 /**
  * backup structure step in charge of calculating the categories to be
  * included in backup, based in the context being backuped (module/course)
diff --git a/backup/moodle2/restore_plugin.class.php b/backup/moodle2/restore_plugin.class.php
index b90bcdf6fdd..31a94f50e9f 100644
--- a/backup/moodle2/restore_plugin.class.php
+++ b/backup/moodle2/restore_plugin.class.php
@@ -34,12 +34,24 @@ defined('MOODLE_INTERNAL') || die();
  */
 abstract class restore_plugin {
 
+    /** @var string */
     protected $plugintype;
+    /** @var string */
     protected $pluginname;
+    /** @var string */
     protected $connectionpoint;
+    /** @var restore_structure_step */
     protected $step;
+    /** @var restore_course_task|restore_activity_task */
     protected $task;
 
+    /**
+     * restore_plugin constructor.
+     *
+     * @param string $plugintype
+     * @param string $pluginname
+     * @param restore_structure_step $step
+     */
     public function __construct($plugintype, $pluginname, $step) {
         $this->plugintype = $plugintype;
         $this->pluginname = $pluginname;
@@ -58,9 +70,11 @@ abstract class restore_plugin {
         $methodname = 'define_' . basename($this->connectionpoint->get_path()) . '_plugin_structure';
 
         if (method_exists($this, $methodname)) {
-            if ($bluginpaths = $this->$methodname()) {
-                foreach ($bluginpaths as $path) {
-                    $path->set_processing_object($this);
+            if ($pluginpaths = $this->$methodname()) {
+                foreach ($pluginpaths as $path) {
+                    if ($path->get_processing_object() === null && !$this->step->grouped_parent_exists($path, $paths)) {
+                        $path->set_processing_object($this);
+                    }
                     $paths[] = $path;
                 }
             }
@@ -258,4 +272,13 @@ abstract class restore_plugin {
                'plugin_' . $this->plugintype . '_' .
                $this->pluginname . '_' . basename($this->connectionpoint->get_path()) . $path;
     }
+
+    /**
+     * Get the task we are part of.
+     *
+     * @return restore_activity_task|restore_course_task the task.
+     */
+    protected function get_task() {
+        return $this->task;
+    }
 }
diff --git a/backup/moodle2/restore_stepslib.php b/backup/moodle2/restore_stepslib.php
index 0d6518d3bfb..51fbbb1a325 100644
--- a/backup/moodle2/restore_stepslib.php
+++ b/backup/moodle2/restore_stepslib.php
@@ -5323,10 +5323,9 @@ class restore_process_file_aliases_queue extends restore_execution_step {
 
 
 /**
- * Abstract structure step, to be used by all the activities using core questions stuff
- * (like the quiz module), to support qtype plugins, states and sessions
+ * Helper code for use by any plugin that stores question attempt data that it needs to back up.
  */
-abstract class restore_questions_activity_structure_step extends restore_activity_structure_step {
+trait restore_questions_attempt_data_trait {
     /** @var array question_attempt->id to qtype. */
     protected $qtypes = array();
     /** @var array question_attempt->id to questionid. */
@@ -5378,21 +5377,21 @@ abstract class restore_questions_activity_structure_step extends restore_activit
     /**
      * Process question_usages
      */
-    protected function process_question_usage($data) {
+    public function process_question_usage($data) {
         $this->restore_question_usage_worker($data, '');
     }
 
     /**
      * Process question_attempts
      */
-    protected function process_question_attempt($data) {
+    public function process_question_attempt($data) {
         $this->restore_question_attempt_worker($data, '');
     }
 
     /**
      * Process question_attempt_steps
      */
-    protected function process_question_attempt_step($data) {
+    public function process_question_attempt_step($data) {
         $this->restore_question_attempt_step_worker($data, '');
     }
 
@@ -5412,8 +5411,7 @@ abstract class restore_questions_activity_structure_step extends restore_activit
         $data = (object)$data;
         $oldid = $data->id;
 
-        $oldcontextid = $this->get_task()->get_old_contextid();
-        $data->contextid  = $this->get_mappingid('context', $this->task->get_old_contextid());
+        $data->contextid  = $this->task->get_contextid();
 
         // Everything ready, insert (no mapping needed)
         $newitemid = $DB->insert_record('question_usages', $data);
@@ -5569,6 +5567,17 @@ abstract class restore_questions_activity_structure_step extends restore_activit
             $this->add_related_files('question', $filearea, 'question_attempt_step');
         }
     }
+}
+
+
+/**
+ * Abstract structure step to help activities that store question attempt data.
+ *
+ * @copyright 2011 The Open University
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+abstract class restore_questions_activity_structure_step extends restore_activity_structure_step {
+    use restore_questions_attempt_data_trait;
 
     /**
      * Attach below $element (usually attempts) the needed restore_path_elements
@@ -5612,7 +5621,7 @@ abstract class restore_questions_activity_structure_step extends restore_activit
     /**
      * Process the attempt data defined by {@link add_legacy_question_attempt_data()}.
      * @param object $data contains all the grouped attempt data to process.
-     * @param pbject $quiz data about the activity the attempts belong to. Required
+     * @param object $quiz data about the activity the attempts belong to. Required
      * fields are (basically this only works for the quiz module):
      *      oldquestions => list of question ids in this activity - using old ids.
      *      preferredbehaviour => the behaviour to use for questionattempts.
@@ -5674,7 +5683,7 @@ abstract class restore_questions_activity_structure_step extends restore_activit
 
         $data->uniqueid = $usage->id;
         $upgrader->save_usage($quiz->preferredbehaviour, $data, $qas,
-                 $this->questions_recode_layout($quiz->oldquestions));
+                $this->questions_recode_layout($quiz->oldquestions));
     }
 
     protected function find_question_session_and_states($data, $questionid) {
@@ -5734,6 +5743,7 @@ abstract class restore_questions_activity_structure_step extends restore_activit
     }
 }
 
+
 /**
  * Restore completion defaults for each module type
  *
diff --git a/backup/util/plan/restore_structure_step.class.php b/backup/util/plan/restore_structure_step.class.php
index bffc7b75290..3fe1978deff 100644
--- a/backup/util/plan/restore_structure_step.class.php
+++ b/backup/util/plan/restore_structure_step.class.php
@@ -496,9 +496,9 @@ abstract class restore_structure_step extends restore_step {
         // Now, for each element not having one processing object, if
         // not child of grouped element, assign $this (the step itself) as processing element
         // Note method must exist or we'll get one @restore_path_element_exception
-        foreach($paths as $key => $pelement) {
+        foreach ($paths as $pelement) {
             if ($pelement->get_processing_object() === null && !$this->grouped_parent_exists($pelement, $paths)) {
-                $paths[$key]->set_processing_object($this);
+                $pelement->set_processing_object($this);
             }
             // Populate $elementsoldid and $elementsoldid based on available pathelements
             $this->elementsoldid[$pelement->get_name()] = null;
@@ -510,18 +510,22 @@ abstract class restore_structure_step extends restore_step {
 
     /**
      * Given one pathelement, return true if grouped parent was found
+     *
+     * @param restore_path_element $pelement the element we are interested in.
+     * @param restore_path_element[] $elements the elements that exist.
+     * @return bool true if this element is inside a grouped parent.
      */
-    protected function grouped_parent_exists($pelement, $elements) {
+    public function grouped_parent_exists($pelement, $elements) {
         foreach ($elements as $element) {
             if ($pelement->get_path() == $element->get_path()) {
-                continue; // Don't compare against itself
+                continue; // Don't compare against itself.
             }
-            // If element is grouped and parent of pelement, return true
+            // If element is grouped and parent of pelement, return true.
             if ($element->is_grouped() and strpos($pelement->get_path() .  '/', $element->get_path()) === 0) {
                 return true;
             }
         }
-        return false; // no grouped parent found
+        return false; // No grouped parent found.
     }
 
     /**
diff --git a/mod/quiz/tests/behat/backup.feature b/mod/quiz/tests/behat/backup.feature
index 99fb72fc49a..eaa8b44c744 100644
--- a/mod/quiz/tests/behat/backup.feature
+++ b/mod/quiz/tests/behat/backup.feature
@@ -34,6 +34,37 @@ Feature: Backup and restore of quizzes
     Then I should see "TF1"
     And I should see "TF2"
 
+  @javascript
+  Scenario: Backup and restore a course containing a quiz with user data.
+    Given the following "activities" exist:
+      | activity   | name   | intro              | course | idnumber |
+      | quiz       | Quiz 1 | For testing backup | C1     | quiz1    |
+    And the following "questions" exist:
+      | questioncategory | qtype       | name | questiontext    |
+      | Test questions   | truefalse   | TF1  | First question  |
+      | Test questions   | truefalse   | TF2  | Second question |
+    And quiz "Quiz 1" contains the following questions:
+      | question | page |
+      | TF1      | 1    |
+      | TF2      | 2    |
+    And the following "users" exist:
+      | username |
+      | student  |
+    And the following "course enrolments" exist:
+      | user    | course | role    |
+      | student | C1     | student |
+    And user "student" has attempted "Quiz 1" with responses:
+      | slot | response |
+      | 1    | True     |
+      | 2    | False    |
+    When I backup "Course 1" course using this options:
+      | Confirmation | Filename | test_backup.mbz |
+    And I restore "test_backup.mbz" backup into a new course using this options:
+      | Schema | Course name | Restored course |
+    Then I should see "Restored course"
+    And I follow "Quiz 1"
+    And I should see "Attempts: 1"
+
   @javascript @_file_upload
   Scenario: Restore a Moodle 2.8 quiz backup
     When I am on "Course 1" course homepage